NefMoto

I have been using the 4bar map sensor without problem, but now I am using 3bar map 038906051A but theres a ~60mbar discrepancy between baro pressure and actual pressure at idle being actual pressure lower.

I remember julex had a similar problem that was caused by DSLGRAD / DSLOFS.

I am using DSLGRAD 658.82 and DSLOFS -63.51

Can anyone confirme if this is correct? and if so, what else could cause this?


(https://s12.postimg.org/498wqt359/3barmapsensor.png) (https://postimg.org/image/ogmcj40mh/)

You logged req pressure, not baro.

baro vs actual

(https://s18.postimg.org/c9ux3x14p/3barmapsensor1.png) (https://postimg.org/image/v26s7hxit/)

I made this simple table for me some time ago and it works well. Hope it's useful for you too. Its calculations are already @3bar, but you'd better know the setup points for your specific sensor.

PS: Your calculation was wrong

thanks, will try those and report back

Does it work?

not tested yet...

658 / -59

With this formula is it possible to change map sensor and have it worked? For example changing the 2550mbar ori with a 3bar or 4 bar? Is it enough?

Sorry the late reply, but it was only possible to test today.

Still the same, whith dgpb values it reads the same diference

with fukenbroken values its even worst.

any clues?

could it be a bad sensor?

first log with dgpb values, second with fukenbroken values

I find various spec values for the sensor, but the more constant is 20-300kpa 0.4-4.65V that gives the DSLOFS/DSLGRAD on the first post.

regards

im using the same sensor
with values i shared (if we talking about non-5120 file)

it shows ~ 960..980 mbar

Log voltage if possible.

when do you measure the engine is off?

On the last two logs yes,  first was runing.

pointless until you log voltage.

Even if you can't log voltage you can calculate what the voltage is at 980mbar by subtracting dslofs and dividing by dslgrad.

then you only need one more reference point, and you can calculate what dslgrad and dslofs should be.

Really, though, you're chasing your tail for no reason. Get a volt meter and get a reading with the car off and the car idling.

will try to measure sensor voltage at diferent pressures, but from previouse logs, engine off or at idle the pressure was the same.

they'll be close because the pressure sensor is upstream of the TB

Ok, so, I did not measure voltage or anything else cause the problem is with a friend's car and we are some kms apart.

I really appreciate all your contribution, but, I don´t think that using anything but the calculated values for DSLOFS and DSLGRAD should be the correct approach. It should not be necessary calibration every time a stock sensor is replaced.

I got another sensor from a friend (known to be in working order) and is reading fine with the calculated values(658.82 and -63.52) so my assumption is that the sensor is just defective, probably could make it read correctly after measuring voltage/pressure but for now I will just throw in a replacement sensor.

thanks

today try
051C map
DSLGRAD 658,8281 
DSLOFS -63,5156
and this calibration correct

(http://i67.tinypic.com/28cmzac.jpg)